Liquid level gauge equipment



April 8, 1941. J TOKHEiM 2,237,461

LIQUID LEVEL GAUGE EQUIPMENT Filed Doc. 2, 1937 zj ohn fl Toiiheim Patented Apr. 8, 1941 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to sealing means, and has generally in View to provide a simple, practical, efficient sealing means especially intended to substantially eliminate loss of vapor through a roof opening of a volatile liquid storage tank of the so-called pulsating or floating roof type in which the roof rises and falls with rise and fall of liquid in the tank and wherein a roof opening is provided to accommodate a tube containing liquid level indicating equipment.

The invention is illustrated in the accompanying drawing, wherein the figure is a vertical section through a liquid storage tank of the pulsating or floating roof type equipped with sealing means in accordance with the invention.

Referring to the drawing in detail, Ill designates a liquid storage tank having a floating roof l8, 1. e., a roof which rises and falls with rise and fall of the level of the liquid in the tank. The roof I8 is provided with oneor more air chambers or pontoons l9 by which the roof is caused to float on the liquid in the tank, and, in accordance with known practice, means 20 is provided to afford a vapor seal between the roof and the tank. Through the roof I8, or through one of the pontoons thereof, is formed an opening, and extending through this opening to, or substantially to, the bottom of the tank, and above the roof to the highestmost position of the latter, is a pipe or tube II to accommodate suitable means for indicating the level of liquid in the tank Ill The pipe or tube H is suitably vented to the atmosphere above the roof l8, as indicated at I3 As illustrated in the present instance, the roof l8 is a provided with a tubular formation 2| through which the pipe or tube ll extends, a cover 22 is provided for this tubular formation, a freely sliding packed joint 23 is provided between said cover 22 and the pipe or tube l I, and extending downwardly from the cover in surrounding, slightly spaced relationship to the pipe or tube II is a tube 24 which is open at its bottom. The width of the space between the tube 24 and the tubular formation 2| is immaterial, inasmuch as said space is suitably sealed at its top as, for example, by a seal 25 between the cover 22 and. the top of the tubular formation 2|. Thus, even though the joint 23 may not be entirely tight, little or no loss of tank vapor occurs because of the very small area of the space between the tube 24 and the pipe or tube l I. In association with any given tank roof having an opening of a given diameter, it may be desired to employ a tube ll of small or large diameter. For a tube ll of any given diameter there is provided a tube 24 of only slightly greater diameter so that only a small space exists between the tube II and the tube 24. Any tube 24 may be sealed at its top to the top of the tube 2|.

Without further description it is thought that the features and advantages of the invention will be-readily apparent to those skilled in the art, and it will of course be understood that changes in the form, proportion and minor details of construction may be resorted to, without departing from the spirit of the invention and scope of the appended claim.

I claim:

A vapor seal for a device for measuring the liquid contents of a tank wherein the tank includes a vertically movable roof having an opening therein and the measuring device includes a vertically disposed fixed tube extending through said opening, said seal comprising a vertically disposed, open-ended tubular member carried by the roof and defining the opening therein, a lateral flange at the upper end of said tubular member, an intermediate, vertically disposed, open-ended tubular member surrounding said tube and vertically movable therealong, said intermediate tubular member being disposed within said roof-carried tubular member and being spaced therefrom to permit horizontal movement of the roof relative to said intermediate tubular member, a lateral flange at the upper end of said intermediate tubular member overlying the lateral flange of said first mentioned tubular member, packing means between said flanges, and packing means between said intermediate tubular member and said tube.

JOHN J. TOKHEIM. 

